It isn't for lack of trying, authorities insist.

"We open and close more investigations than we prosecute," said Fuhrman.

Probable cause

In 2003, a joint state and federal task force was convened to look into crimes within all of Utah's polygamous groups.

"We asked them to come out and take a more comprehensive look at things," Torgensen said. "The agencies came back and said, 'We're not finding anything."'

The U.S. Attorney's Office said it did not develop enough for subpoenas, search warrants or indictments.

"The fact that everyone may think something's going on ... ask Elliot Ness how easy it was," Tolman said. "He knew, and he knew Al Capone was involved. It still took quite a bit. It takes a lot, and it takes a concerted effort. Even though everyone may be clamoring, it doesn't make for a federal case."

Tolman said they still need probable cause.

"No matter what, we still have to abide by the Constitution and our criminal procedure rules," he said.

An attorney acting as a spokesman for the FLDS Church declined to comment on Tolman's remarks but said he could appreciate their approach toward probable cause.

"That's a much more responsible approach than what's been taken in Texas with respect to the Constitution," said Rod Parker.

The raid on the YFZ Ranch began April 3, when someone claiming to be a 16-year-old girl named "Sarah" called a family crisis shelter in San Angelo, Texas, saying she was pregnant and in an abusive polygamous marriage. Authorities are now investigating if the call was a hoax.

When Texas child welfare workers responded to the ranch, authorities said they found evidence of other abuse, including teenage mothers. That prompted a judge to order the removal of more than 450 children from the FLDS compound. They have since been placed in foster care homes across Texas.

Warren Jeffs

Federal prosecutors have leveled a charge against Warren Jeffs for unlawful flight to avoid prosecution.

Jeffs, at the time on the FBI's Ten Most Wanted list, was arrested outside Las Vegas during a traffic stop in 2006. Typically, when a fugitive is arrested, federal authorities dismiss the charge. Instead, Jeffs was indicted by a grand jury.

The 52-year-old FLDS leader was convicted last year in Utah of rape as an accomplice, accusing him of performing a marriage between a 14-year-old girl and her 19-year-old cousin. In Arizona, Jeffs is facing more charges accusing him of similar crimes.

On the final day of the police search of the YFZ Ranch, FBI agents executed a search warrant.